Conventionally, refrigeration apparatus such as air conditioning apparatus have included refrigeration apparatus that use R32 as a refrigerant. An air conditioning apparatus that uses a refrigerant such as R32 is described, for example, in JP-A No. 2004-263995. This air conditioning apparatus is equipped with a hot gas bypass circuit and an automatic opening and closing valve that divert some of hot gas discharged from a compressor and introduce it to an accumulator as a countermeasure in a case where refrigerating machine oil and liquid refrigerant have separated into two layers in the accumulator. Additionally, in accordance with a condition such as the temperature of the hot gas, the automatic opening and closing valve is opened to thereby guide the hot gas to the bottom portion of the accumulator, so that the liquid refrigerant and the refrigerating machine oil that have separated into two layers are agitated and the refrigerating machine oil is returned to the compressor from the accumulator.